Office rental rates in Austin are higher than ever, according to Aug. 4 data released by real estate analysts.

Asking rates for office space increased to $32.83 per square foot in the Austin market and $47.80 per square foot in downtown between April and June, according to a 2015 second quarter report released by Austin-based real estate firm Oxford Commercial, a member of the Cushman & Wakefield alliance.

Those increases represent year-over-year gains of 12.4 percent and 10.6 percent, respectively, making rental rates the highest since Oxford began recording data in the early 1990s, according to a news release.

“Office buildings are selling at historic prices, available spaces are quoting historic lease rates and occupant rates remain higher than ever before,” Oxford Associate Vice President Melissa Totten said in a statement. “New construction continues to dominate the skyline as many buildings are spoken for prior to their respective completions.”

There was 1.08 million square feet of office space introduced to the Austin-area market during the first half of 2015, according to Oxford, compared with 667,901 square feet of office space delivered during early 2014.

In total, Oxford estimates 4.7 million square feet of Austin-area office space is either under construction or recently completed. Nonethless, the firm claims occupancy rates dropped to 9.7 percent during the 2015 second quarter, down from 10.2 percent the same time last year.

Oxford Senior Vice President Brian Butterfield credits major leases from Apple, SolarWinds and Oracle as well as expansions from Google and Indeed for helping expand the Austin office market.

“The impact and ripple effect of these tech titans is being felt in a particularly strong way downtown and West Austin,” Butterfield said in a statement.

Office rental rates are expected to remain high through 2015, and vacancies are anticipated to remain low, according to Oxford.